mdb_call_dcmd()

Invoke
the specified dcmd name with the given parameters. The dot variable is reset
to addr, and addr, flags, argc, and argv are passed to the dcmd. The function returns 0 for success,
or -1 for error. The function fails if the dcmd returns DCMD_ERR, DCMD_ABORT, or DCMD_USAGE,
or if the specified dcmd name is not known to the debugger. The dcmd name
can be scoped using the backquote (`) operator if there
are naming conflicts.